Crescent

Tradition says that “Philip, the father of Alexander,
meeting with great difficulties in the siege of Byzantium, set the
workmen to undermine the walls, but a crescent moon discovered the
design, which miscarried; consequently the Byzantines erected a statue
to Diana, and the crescent became the symbol of the state.”

Another legend is that Othman, the Sultan, saw in a vision a
crescent moon, which kept increasing till its horns extended from east
to west, and he adopted the crescent of his dream for his standard,
adding the motto, “Donec repleat orbem.”